docs: def set_dhw_on(self, until=None):
          """Sets the DHW on until a given time, or permanently."""
          if until is None:
              data = {"Mode": "PermanentOverride",
                      "State": "On",
                      "UntilTime": None}
          else:
              data = {"Mode": "TemporaryOverride",
                      "State": "On",
                      "UntilTime": until.strftime('%Y-%m-%dT%H:%M:%SZ')}
  
          self._set_dhw(data)